Testing press



w. ERNST ETAL 2,326,345

TESTING PRESS Filed Aug. 24, 1940 5 Sheets-Sheet l mvEN-roras WALTERERNST IRA mmwys,

ATTOIQN E'YS Aug. 10,1943. v w. ERNST ET AL 2,326,345

TESTING PRESS Filed Aug. 24, 1940 5 Sheets-Sheet 2 .LA by [RAB QM +$MATTORNEYS Aug. 10, 1943.

w. ERNST ET AL TESTING PRESS Filed Aug. 24, 1940 Sheets-Sheet 3 iNVENTQRS WA LTER ERNST, IRA amwvm,

AT Tora EYS W. ERNST ET AL TESTING PRESS Aug. .10, 1943.

Filed Aug. 24, 1940 5 Sheets-Sheet 4 BY W 5 INVEHTOKIS WALTER ERNST, um43. LAWYER,

Aug. 10, 1943. w. ERNST ET AL TESTING PRESS 5 Sheets-Sheet 5 Filed Aug.24, 1940 K ERNS' .IFLYEHTO wm. ER bY (RA 8. LAWYER,

' raw ATTORNEY-S Patented Aug. 10, 1943 IESTING 'Pn'Es's Walter Ernstand Ira B. Lawyer, Mount'Gilead,

hio,.assignors to The Hydraulic Development Corporation, Inc.,Wilmingtom DeL, aQcorporation of Delaware Application August 24, 1940,seri i No.

'14 Claims. 7 (01. 73 -51);

This invention relates to presses, and in particular to hydraulicpresses for testing articles which are tobe subjected'to or have toworkunder high pressures, as for instance shel1s,lva1ve Lfl heseend otherobjects-and advantagesof the invention will ap ear more clearly from thefollowing specifi :ation in connection with the accompanying drawings,inwhich: f V

Figure 1 is a frontiview ofjan'embodiment of bodies, fittings,cylinders, etc. V 5 a testing press according to' the invention.

It is an Object of the invention to provide a Figure 2 isa side viewofthe pressshown in test n Dressjfor testingjhollow'articles in} whichFigure 1. i f i V the article to be tested is subjected to hydrofLFigllre 3'sh0 ws diagrammatically the general. staticpressure; V Varrangementof .the piping and control system,

Another object of, the in'ventionconsists in the Figure 4jis asection,along the line 4-1: of provision of a hydraulic testing press fortesting Figure 5 showinga'structural detail of the press hollow articlesin which hydraulically. controlled for operatingthe shields protectingthe operator pressure is exerted on fluid filling a recess,' b,ore,against injuries. 1 -1 f 1 1, e li of the article to be tested. 7 cFigure 5 v.is a section alongfthe lineii'of It is a further object ofthe invention to pro- '15 Figure 4 I V I v p i a testing press. s 'setforth above, which Figure "6 is a section'alongthe liiie' a+ anrcomprises a plurality of cYIin B -Pi Q B .Figure 4, however, With'theprotecting shields in blies operable in'a predeterminedsequence'for.clgsed tion, F .I i reeeiving workpiece to -te e e- Figure"TiIIuStratesthe testing plungerproper twgenland 1effectilng tthetestingoperation. I .orjntensifiefj g l til ano her 0 jec of'rtheinventionconsists I r in theprovision of arhydraulic testingp iQ wgfi tl'f gre ss o figiJihfnfZfififi?-- testing hollow articles, in which thek Piece Figure 9 is a section along the line ii -90f is-adaptedto becovered byprotective means so e; and I" j j 1 I as to prevent injuriesto the operator in casethe g 1b Shows a 'f d d fi n gwh hworkpiece-Should break comprises nieansfor filling the work piecet'o Itis also an object the invention to provide be tested -with fluidafter-it has been placed on e a testing press, as setfforth in th'epreceding th-iestinmachjne a p Q paragraph, in which theworkjpiece. ishydrauli (e I p v j i a g j callym-oved into its testingpbsitiohtvhilesimllljwe :1 en r lv rm qem g t li l i m mf the DI'O t Q ms. o f The testing prs s. according to' the present im i P$I3- n l 1s q:vention comprises in generaltwooooperating hy- .I 1 99?? obJect ofjhemventlon 9 7 h draulically operable cylinder-piston assemblies, ig 1 of9 2F 5 r m 191 9 one ofwhich ;'c1a1nps.-th e article to be tested into'i 5 2 means Pa covenfig 30 its tesltingposition, .-.while the othercylinder- ;'P F we. piston-assembly a tu t -a t testing e mpvable'mtooperatlve positron-at Select-ave sure upon fiuid'fillinga hollowspace'in the article rate. i

FA still furthe'r'object of theinvention consists F i' --i-' l e m g r sgr inproviding a hydraulic testing bress'for hollow 40 ,s-emmy i g i' if. c articles in which the clamping pressure for holdwhen hclampmg'opegatmn 'q m the work piece in its tes'ting positionis variig gfi ggg 25 5? able. Still another object of the invention consistsposslble imlmes q h w p qer 1 d I in theprovisio'n' of atesting press'f-orl10l1o w45 b e m ham f0rlactuatmg e pr articles which comprises'a-hydraulic system for *teotlve h i s f J is abl 's i! is to v thfillingthe work piece tobe testedjwitltfiuid'after 9 Tate atiwhlch Q 3of h j the work piece has been placed on the'testing -1 efl eCteCl. Theinventlon IthBImQ Q press. 7 f 1 comprises means.forvarying'ftheclamping pres It' is another'object of the invention to prosure a e -i-w k p e ee nvp rl vide a press; as set forthiin the'preceding para-'cat'edf nd Operation h i e sifi r a graph, which includes 'adjustablefautomatic. beenin a ed'. f nieasuringmeansfor meting out a,predetermined According to a further development of the 1111;-qua'ntit'yof fluid for filling the'article' to be tested. I vention,-the"press is provi wi h anadi '55 measuring devicewhich'automatically'rnetes out' surface 3,1. The er nd-M the i-{l ensifi-.-9y ind l se L asket I 81 3 pr ss-e sed gasketttain a a o ewlindr flwmeeneqtsqmi 7 he he? i a i by screws 55. The gland 3B, colla g a adiacent it -s berewier receiving a sealfd' acct a predetermined quantity'offluid for filling the article to be tested 7 a Structural arrangementReferring now to the drawings in detail, the

press, according to the invention, comprises a press bed 10 and a presshead H interconnected U with eaehother by strain rods il l'andgnutsMounted'on the press bed is an electr-omotor M for driving a variabledelivery pump I5. The

motor and pump I5 are drivinglyconnected by. 'i' means of a coupling 16.I S 7 pump l5 which is provided with a safetyfvalve The variabledelivery ing cylinder 61 at a predetermined ratio with regard to thepressure applied to the intensifier plunger 28. The conduit 60 comprisesa check valve 69 and communicates with a conduit It! comprising a'checkvalve H and leadingto the bore 12 in the pressing cylinder 61. Thepurpose'of' the check valve 69 consists in forcing jthefluid coming fromftheifouiieway'valve 24 to pass through "the reducing valve '64. Thecheck valve 1| prevents thefiow of fluid from conduit J 19 to theretraction side of theclamping plunger r gii while permitting the'fiowof fluid in the re- 18 has its suction side connecttfed'vbmmeans of aconduit IS with a fluid or fsurgeitarik ifil The pressure side of thepumpwli-is cdnnecte'd bymeans of a conduit 2|, leading to the'safetyvalve l8 with a check valve 22; inturn is connected by conduit 23 with afour-way valve I 24, of any convenient structure. A conduit 2-5 leads rm the ten m -va e 2 te he; l ne n rti t 9f the e. 21. The'cylinder,

' ec t stin P un e 3-- an pi to .7 a smaller lower surface 3fl and alargerj upper r t n rbm ul 'eitl i ev r cylinder 21 is likewiseprotectedia hum s. a 1 9 21212 tiicomp le sed .7

of screws '31, vis con '36 which, by means r t icr ic ez a ee; with a 90awh are 38 isrpoaneceetam .9 Bi

member 39 are provided withb 40* T12"rspeetivelyfithrough" which themidi-gee? s may pass. The bore 40 jof the glandgfifi annular recess; 43-eonne' 'dwith a bore 1 one ing tothe qutsid lower. portion of the recess4sco;nmu

C through-bores fl itn aa an miar recessrecbnt e here; rj r jti iecellar eaa 'rhe bore's communicat through-'- a passa eway 1:9

' scopes a's-tationa'ry booster 14.

verse direction as soon; as thepiston portion H; in its-downwardmovement or retraction stroke, has: passed the bore 12. The clampingplunger-jQ has-acylinder bore E3 in which telehas a bore lipassi gthrough its entire length and communicating with a conduit 16 leading to*a g-auge 11 (Figure 1) r for indicating the booster Pre su e Th a-conui is conn t wit a ead i 1M. iqh nits tu n cdr muni e s wit namel auge fr ind ca n th dd qna clam ng. re e x rt ibr u d acting-up n the lowerportion of -itheclarnping lunger'fiii.

' f tre'elanipfng cylinder; 61 fp' fdi by lind Fiieaidi tad can a a n t;t e ylind r 61.

Branching on? from the conduit 1931s; (a' con- 7 a chec va v it; a a t dto in er o "bi t Surge ifihiatihg Withtheprssure side or the variable isa conduit ompr s a nd leading o a f u rw v; v v a yvalve 86 is adaptedtocomv aflth el .'a condui 81 w h a re 8.8, 1 9-uPP R i q ithee am cy i d,1. A 'ifurtl'ier conduit fis communicates on one hand with 'P ef HI-WY-Y lK nd n, h -O h with a bore in. the fitting m cennected with V thecollar 38;}; means-of sor'ews 52. The con 'tion of which th workpiecei'i'fl'nra'y be clamped. willbe seen from Eig'ure e b'or'e win ther mgmembetes is taperd 's l iatiworlg ipieces' rot-various sizescaifsbeffclanipedagainst the gasket 56. To illustrate thisi-Fig ure 7shbwsfin dotdash lines, a shell .58 ofgreater 'dimensions than'theishell or the. work =piece 51] a i i .Tiiefour-way valve zl isiurthermore connected .iby means voi acon'duit'6flland oonduit6],;brahc'h- 1118f ofiifrom'cohduit BlI -v'vithi-a;:bore 62 innth'cylinder, headiwhich boreile'adsito the upper .por;

-' ticn .of the cylinder 231.15; Branching off from vthe "mmm t dilis alconduitiliileadingi-tlo a reducing Ygwe H;

ed on the press bed In. The reducing; valve,

Wh h-remot arly in; e su e 8;.1 a dap 9 mainta suresexerteids by, r

9, 2.. c n the c ampe .10 Inc s-nos of a conduitlifi; is.fimmunticatclwithv a portififi in-the ew epert enlpttb 'clampineiqr inceimmune Witha shield operating cylinder Silv through nfit fi fch k6 1 e rI Th ;911, t" 1% adjus able by s t o 't dn h 1 91% the flu d Pass nthr'eu conduit 89 may enter the-bored; leading to the bore. i o the hi lii at n$eY i der.- Q-. T

Q l gr iiifini t p si q n b ar l: 2

wh; n at t s en ime Pro ect he ierewgir m d ma p Qommi i at ne-w t thway- 12f which s eon tin usl u ed .hy-asrzr he er adet xmis passa edaall. 1,1,2 n- A ,7 a, l2; c a n t heseat I24. The springi23 is arrangedin a'bore provide n" t2'5 om uni et aethr u h passa eway izfiwi h V meami e; 8a, The er at or h n an eqm r s a step ;S,5.hev. ne unte her inaguiding member 96 witha boreSl through which isconnected; with: arack"99,5 passes through a rack n 9 1: p ssed a a n t the di m mberfifiby;.a.guiding member ML ,The rack- 99 is slidable on the surface I02 ofthe arm l03.sup-

' eitheieyl n eefla he a m. -nta car ies a is a spring L96 which engageson ,one handthe end surface [01 0f the track 99, and on the other handan adjusting nut I08 threadedly mounted n; a corre p nd n thread; ma ofthesha t' 1 4. The-nut lpiiyis secureddnyits,position,by a sec nut HotBy -adjusting the nut H18 :the

upon the plunger 98', caus movemen't or The booster T4 a 'r -"s' so, ato var h of the spring H35; may ;be,varied, ithereby determin ng-c, thepressure. -Which,-: When-"acting Similarly, the shaft has keyed theretoa lug II8- carrying a semi-circular shield II9 sothat rotation of theshafts I12 and H5 is adapted to swing'the shields H1 and I I9 towardeachother for e'nclosing the workpiece, or to swing the shields awayfrom each other to enable removal of the work piece. Referring now toFigures 8 bore I2! and a cylinder bore I28,:se parated from each otherby a recess I29, (Reciprocably mounted in'the cylinder bores I21 and I28is a stepped piston I39 with piston portions I3I and I32, separated fromeach other by an annular groove I12. 7 The piston I39 has a bore I33pass: 1 .ing through the'entire length of the piston,

whereas another bore I34 passes from the upper portion of the piston I39to a boreil35 leading to a recess I36 communicating through a bore I31with .the conduit 63' The bore I34 communicates through a transversebore 7 I13 with the groove I12, while a valve member I38 threadedlymounted inthe bore I34 determines the section through which fluidentering the bore I35 may pass into the groove I12 and from there-intothe recess I29.- The cylinder bore I21 communicates with the conduit-55. Threadedly connected .to the cylinder portion I23 is aitubular-member I39 pressing a gasket I49 against the cylinder portionI26 so as to avoid leakage b-etweenthe tubular member I39 and thecylinder portion I26. -The tubular member I39 has a threaded bore I4which is engaged by a hollow plug MZ abutting one end of a spring I43,while the other end of thespring I43 abuts 'the'upper portion of thepiston I39; To prevent'undue manipulation of the nut I 42 a cap I44 isthreadedupon the plug I62 so asto cover the latterwhile simul--taneously pressing a gasket I 45 between the lower end of the cap I44andthe upper end of the tubular member I39.-' As will be seen fromFigure 9, the-tubular member I39 hasla transverse bore M9 communicatingthrough a conduit I I'I with the surge tank 29, while communicatingthrough the passageWay 'IAB with the bore I49 'of the tubular memberI39; The bore I46 has adjustablylmountedtherein a choke member I50 forvarying-the passage through which the fluid from the passageway I IB'hasto pass into the conduit I41. To protect undue manipulation of the chokemembers. I50 the head I5l "thereof is protectedby a cap I52 threadedinto the tubular 'Whilea work piece, when tested on arma'chine describedso'far, has to be filled with fluid before member it is placed on themachine, the embodiment -illus- V trated in FigureilO "shows a'hydrauliccircuit which allows filling the work piece with 'fiuid after it hasbeen placed on thepress bed. According to this embodiment, theintensifier plunger ZBhas an extension I53passing through the cylinderhead33. The bore I5 3 passes'from' the upper end of the extension I53 tothe'l ower end of the-intensifier plunger'28 and is connected with apipe I55 leading tea twoway valve I53; The pipe I55 maybetelesco ped inthebore I53 or, if.desired, may be made flexible; I The valve I 55' 1 isadapted,. when 'iopened', to communicate and 9, showing the reducingvalve 64 indetail, the reducing valve comprises a cylinder portion I25with a cylinder adjustable pipe I59 telescoped therein. The pipe I53 hasa scalethereonso as to indicate its .posivtion relative to the overflowpipe I59 which is connected through a conduit I6I either to the. surgetank ZjBor to anothenexhaust: The con- I tainer I58 furthermorecornmunicatesvwith a conduit I 32' comprising a two-way :valve 163 I vwhich; when opened; communicates throughthe conduit i59 either withthe-pump I5 or with an independent source of fluid adap'tedtoasupplyfluid to the container I53; 1The'valves I63 and I 56. are interconnectedby means of a linkage I in such 'al nanner that; operation of thelinkage Y Ififiwill close one valve-while opening the other valveandvice versa. Therefore-if for instance the valve IES'is closed-fluidwill'pass'through the valve I33 into thecontainer I58 and fillthelatter'up to the level determined bythefiextent' to which the pipe I69protrudes beyond the'pipe I59. .It will be evident thatthe'pipelw issoadjusted that the quantity of fluid admitted to the container I53correspond to the:,quantity of fluid necessary for fllling'the workpieceto be tested. When fluid has fllled'the container I59 V to thepredetermined level, further fluid will flow to the surge tank or toexhaust through'the conduit'IEI. Preferablythe containerI58-c0mmunicates through a conduit I33 with a gauge I91 indicating thefluid level in the'container I 58. The operator "may; at adesired time,open the Y valve I53 and-close the valve I533 so that fluid accumulatedin'the "container I581. will then be unloaded through-theconduitI55'into'the bore I54'from where the fluid will flow into the recess ofthe workpiece to he'tested whereupon the valve I55 is again closed andthe'valve- IE3 is again-opened so thatthe container "willfagain fillwith fluid. Otherwise Figure 10 corresponds I in its construction to thepress describedin con 7 nection with Figures 1 to 9. s

7 Operation In order to-carry out a'testing operation and providing thatall partsoi the machine occupy the position shown in Figure' B, theoperator" starts the motor" l3 and, thereby, also the'ipump I5. Pressurewill now develop in theconduit t l." As long as the four-way valves 23'and95 are closed,- the pressure cannot pass beyondthe said v twovalves.

Assuming now-that the Work piece 51 has been I filled with fluid andplacedon a receiving mem niping plunger 53',. .the'operato'r shiitsthelover I =3 (Figurel) soas' I to open thefo-ur-wa'y valve 83 and toallowfpres v sure fluids-to passfrom the conduit-.83 'throughthesfour-"way valvefid and the conduits 99 and her I 68 connected withthe ol I6 through the bore l5ir'i'toith'e booster cylinder 13; Thepressure infthe booster cylinder II then caus'es thev clainping plunger38to move upwardly y from its lowermost position-shown inFigure 3,

thereby lifting the'work piece 5? so that its open endis pressed'againstthe gasket'53-betweeh .the collar'33 and the ringmember 39. The suction'created'in' the lower-portion of cylinder 91 during this upwardmove'rnent'of plunger'fiil causes fluid itdfl'owffrom the' tank 29through conduits 53.2

and 'Iliaintothe' cylinder:fi'l thereby fllling the space" beneath the'piston qportion I'I. While pressure is applied to the clamping plunger.63, pressure fluid also passes through the'conduit'lii 7 intothe'shield -operating 'cylinder 99: where it plung'erfia causesmovementofithe'rack 99 which v rotates the gear H1 and thereby also thegears U3 and I UL? Rotation-of. the gears, i; and l [4; causestheshields-J t1: and ljlfl toaswing toward each other therebyenelosingqthe workpiece According to the adjustmentofthe chokenfll' andthe passagewaymade-available thereby to the fluidpassing through. theconduit 89; the closing operation oi the shields ill and H9 will beeffected with. a desired speed;

When th work piece-is securely clamped between the gasket 55 andthevreceiving: member Hi8, the operator manipulates his hand lever llfl(Figure 1') to open" the valve 24; for admitting pressure fluid from theconduit 84. into; the con- 33iQ3 m actsauponi the plunger 98.; Movementof the piece may newbie-removed The fluid expelled by duit 60 from-whereit. flows through' the con-, 7

duit (il and. the bore 62intov the upper;portion of the intensifiercylinder 21 where it'acts upon the intensifier piston head 29. It willbe noted that no fluidcan pass from, conduit Bfl through check valve 69into conduit'llla. As soon as pressure begins to build up in cylinder2], this pres-' sure is conveyed through conduit 63 and bores I34 and H3beneath the piston I32 of valve 64; so as to lift the piston I32 and toestablish'fluid connection between .the, conduits63 and 65. Pressurefiuid then passes from the conduit 6Q through conduit 63', reducingvalve 64, conduits G and ifla and through the bor BB into thelower'portion of the clamping cylinder '6] so that pressure is appliedsimultaneously to the intensifier plunger: 28 and. the clamping plunger68. r a

The reason to apply full clamping pressure to the plunger 98. during itsreturn stroke passes through the conduit 89 and the opening H4 of ,thefour-way valve 86 intovthefluidtank 2B.

7 'Ihe 'esc'ape-of pressure ffluid from the shield operating cylinder901s. facilitated by. the pro.- visicn; of the. spring loaded checkvalve I22, 1.23, which: by-passesthe,choke-9t; I a

.As previously; mentioned, ,the reducing valve 6.4 vserves formaintaining .theclamping pressure during the testingopeiiation at" apredetermined atio with. re ard. t the p ssure a pl ed t the ntensifi n.ther wo ds. w en t pr ss re actingon the piston 11 increases, jalisqthepresr sure. n e pi to a 3| the n ens fi r plunger28 increases. v a VA Wil be seen fr m F ure fluid passi through the conduit 83 enters thbore I and then passes around the lower end of the choke member L34through the bore H3, into the groove E12 from where it flows into therecess 1 29. Here the pressure fluid acts upon the piston portion i3;and lift ;the latteragainst the action of the 7 spring 143' so thatfluid may pass from. the conduit 63 through the -bore lii'l directly tothe con the'clamping plungernfilionly simultaneously withapplyingpressure-to the intensifier plunger 28 and not simultaneouslywith the admission of clampin that in the latter instance the sealinggasket EJmight be crushed or cut.v However, by simultaneously applyingpressure to the clamping cylinder 68 and the intensifier plunger 28 theclamping pressure exerted byv-the clamping piston .68 is partly balancedby the, pressure exerted by the intensifier plunger 28;

, The intensifier plunger 28 now enters the fiuid filledrecessin thework piece and squeezes aportion otthe fluid through the recess 48 andbores 41:,49, 59, and 53 into the gauge 54 thereby informing theoperator of the pressure exerted by the intensifier plunger/28 so thatthe operator may finish his testing. operation atthe attaining pressureto the booster cylinder- 13 consists V ment "of a predeterminedpressure. "When the testingpressure has reached the desired amount, theoperator shifts the valve 24 to the position where fluid pressure willbe admitted through the y conduit 2 5 into the'lowerportion of theintensifier cylinder 271st). that the pressure developed below thepiston head3l willlift, the intensifier plunger,

thereby relieving the'pressure in the'wo'rk piece.

The fiuidfdisplaced by the upward movement of the intensifier plunger 28passesthrough the conduitfSUIIand the opening. ill of the four-way valve24, into the surge tank 20, I

. a When the; intensifier pressure has beenrre duced, the operatorshifts thevalve 86,so asto allow pressure 'fluid to pass from theconduit 84 into the conduit :81 fromwhere it flows into the upperportion of the clamping cylinders? thereby causing retraction of theela-mpingplunger 63. T Thedisplaced fluid in the lower; portion of theclamping cylindeni. e., beneath theipiston" H, escapes through both thebore 68. and the check 7 valve H into theconduit fiilirom'where it. pass through the opening ill of. the four-way: valve duit "f The pressureithe conduit 65 is conveyed through the bore j33 to the upper portion ofthe'stepp'ed piston I30 where it supports the action'ofthe fspring M3.After some time the stepped piston JBQ occupies a balanced position inwhich a predetermined quantity of pressure.

fiuidpasse's'directlyfrom the conduit 63 into the conduit. 55;' As willbe evident from Figure 9, a small quantity of fluid continuously passesfrom the bore l4l through'the passageway I48 and the bore lflfi totheconduit I41 leading'to the fluid tank 20. This fluid-iscontinuou'slyreplaced by-fluidpassingthrouglr the conduit 63. When the piston 11",during itsdownwardor retracting stroke; has'again reachedthepositio'n'shown in Figure 3; checkv'al've 'Hiestablishes fluidconnec= tionb'etweenthe bore lzxandtconduit '70; so that the delivery oithe pump l5' through conduit 81 into theuppenportion of'cylinder 6T1 isdischarged throughbore 12, chec-kvalve l-lgcon'duits HI, Bfiflandopening |-TI-= into. the tank 2'0.- Piston 11,, therefore, comestoahalt. 7 All parts new again occupy the positionshown in Figure 3. 1

- It will be understoodthat we desire to comprehend within our inventionsuch modifications as come withinthe scope of the claims'and theinvention. a I

Having thus fully described ourinvention, what we claim as new anddesire vto secure by Letters .1. In a press, fluid operable meansforhydraulically supporting a work piece and clamping it against anabutment,v mean for admitting pressureefluid to a restricted'area-ofsaid fluid operrahle-means to cause the latter tO'EXGItfl re- ,stricted,clamping pressure upon said work piece,

fiuidloperable pressing means adapted to enter recess ;in saidwork piece forexerting pressure upon fluid filling said recessin the work piece,

and means responsive; tov a" predetermined .pressure acting on, saidpressing means vfor admitting pressure fluid to ansincreased area ofsaid fluid operable means for causing the latter-:to exert full clampingpressure on said work piece.

2. In a press, fluidoperablemeans for lifting awork piece and clampingit against a abutment, means for admitting pressurefluid to a restrictedarea of said fluid operable means to cause the latter toeXert arestricted. clamping pressure upon said work piece, fluid operablepressing meansadapted to enter a recess in said workpiece for exertingpressure upon fluid filling said recess in said work piece, firstconduit means for admitting pressure fluid to said restricted area,second conduit means for admitting pressure fluid to said pressing meansindependently ofthe supply of pressure fluid to said'restricted area,third conduit'meansfor admitting pressure fluidto an increased area ofsaidfluidoperable,

clamping means, and fluid pressure, responsive means responsive to apredetermined pressure acting on said pressing'means for hydraulicallyinterconnecting said second and third conduit means to maintain a.predetermined ratio betweenthe pressure acting on said pressing means.

and the pressure acting on said fluid operable clamping means while saidwork piece'is clamped.

3. In a press, hydraulically operable means adapted to movably supporta, work piece and to clamp it against an abutment, said means comprisinga plunger witha' booster area and'a'main area, hydraulically operablepressing 'means adapted to enter a liquid filled recess in 'saidworkpiece for exerting pressure upon said liquid,

pressure in said second cylinder-pistonassembly for.automaticallyadmitting'pressure fluidtosaid I main area. .7 6. Inatesting pressyahydraulically operable clamping plunger, workpiecereceiving means ;connected' to saidplunger, aphydraulically Opervalvemeans operable selectively to supply pres- 7 sure fluid to-said boosterarea and saidpressing means, and controlling means operable in responsetoa predetermined pressure acting onsaid pressing means forautomatically admittin pressure fluid to said main area. 7

4. In a testing press, apress bed supporting a stationary clampingcylinder, a fluid operable clamping plunger reciprocably mounted in saidable testing plunger adapted to be, actuated inde:

pendently of said clamping; plungerand to enter a recess in awork pieceplaced. ,uponsaid work piece receiving means, a fluid source adapted :to

supply pressure, fluid .tosaid plungers, and control means,hydraulically connected pwith said testing plunger, for permitting ofvonly a limited fluid; pressure being exerted upon. said clamping plungerprior to a predetermined fluid pressure said ltesting plunger and thepressure actingon said clamping plunger during .the actualtestingoperation of said testin plunger. V I

M7. In a testing 'press, apress bed, a clamping cylinder supported bysaidpress bed; a double 1 acting clampinglplunger',reciprocably mountedin said clamping cylinder and :comprising-qa main area and aboosterfcylinder, a booster plunger rigidly connec'tedwith saidclampingcyhnder and telescoped in said'booster cylinder, said clampingplunger being adapted movablyto support a work piece. and to clampthelatter againstyan abut- I 'ment, a testingplungerarrangedin alignment,with' said clamping cylinder and-adapted to enter a recess in saidworkpiece, a fluidsourceiorsupclamping cylinder and having a booster areaand a main area, a press head, a testing cylinder supported by saidpress head, a fluid operable testing plunger reciprooable in saidtesting cylinder, a fluid sourceadapted to supply fluid to'said clampingcylinder and to said testing cylinder for actuating the plu'ngerspertaining thereto, first controlling means for admittingfluid fromsaid-fluid source to said booster area, secondc'ontrolling meansoperable independently of said first controlling means for conveyingpressure fluid from said fluid source to said testing plunger 1,supportingflmea-ns adaptedmovably to support a; hollowwork piece and tohold the-latterin testplying pressure-fluid, and pressure responsivecontrolling means for automatically preventing the supply. of pressurefluid to the main. area of. said'clamping plunger prior to theapplication of a'predetermined pressure to, said testing,- plunger. 8;In a, testing press,hydraulically-[operable ing -position, hydraulicallyoperable pressing .to move the latter toward said clamping plungenfl andpressure responsive means hydraulically connected with said testingplunger and adapted in response to a predetermined pressure on saidtesting plunger to convey pressure fluid to said main area. r

5. In a testing press, a first and a second hydraulically operable.cylinder-piston-assembly arranged in alignment with each other andadapted to act in a direction opposite with respect to each other, afluid source adapted to supply pressure fluid to saidcylinder-pistonassemblies, said first cylinder-piston-assembly having aplunger with a main area and a booster area and being adapted to clamp aWork piece against the cylinder of said second cylinder--piston-assembly, andthe piston of said second-cylinder-piston-assemblybeing adapted to enter a recess in said work piece, first controllingmeans for controlling the flow of fluid from said fluid source to saidbooster area, second controllin means independent of said firstcontrolling actuating'means for reciprocating said'rack, a fluid sourceadapted to supply pressure fluid-to.

means adapted to enter. said hollow work piece 'ior exertingv pressureupon fluidfilling said work piece, shielding :means ;compr'ising:.two.semicircularshields movableztowardi-eachother for shielclingithev workpiece, each of, said shields being rotatablyconnected with a pinion of agear train including a rack, hydraulically operable each oi-said means,and control means for concomitantly admitting fluid from said fluidsource 'work piece, a gear operatively connected with'said to saidsupporting mean means. l

9. In a testing press, a press bed, a clamping and said actuatincylinder piston assembly associated. with said i press bed and adaptedmovablyto support a hol-- low work piece and'to hold the latter intesting position, a press head supporting a testingcylinder-piston-assembly arranged in alignment with said clampingcylinder-piston assembly for exerting pressure on fluid filling saidhollow work piece, swingable shielding plates-adapted to be 7 movedrelative to each otherso as to shield the shielding plates, ahydraulically operable rack meshing with said gear and adapted torotatethe latter for selectively closing-and openingsaid shieldingplates, and hydraulic meanslfor -a'ctue atingsai'd rack, said clamping.cylinder-pistonv assembly assembl and said testing cylinders-piston- 10;In a testing press; a" clamping madapiston-assembly adapted to movablysupport a' hollow work p'ieceand tohold the same in testing position; apressing cylinder-piston-assembly arranged in alignment withsaidclamping .cylinder-piston-assembly for actuating; pressure on fluid insaid hollow work piece, shielding means operableselectively to shieldsaid work piece and uncover the same, a shielding Y means actuatingasses-4:5 V

automatically establishing and, maintaining a predetermined ratiobetween the clamping pressure applied by saidYsupportin-gmeans and thepressure applied by said pressing means during a testingoperation.

13,; Ina testing press hydraulically operable clamping means adaptedmovably to support a hollow workpiece andto hold the sameintestcylinder-pistoneassen bly,.a fluid source ,forsupplyingpressu refluid, controlling means for controlling the supplyof pressure fluidfrom said fluid-."source to'said clamping cylinderapi'stoning position,a hydraulically" operable testing plunger adapted to enter said hollowwork piece to exert pressure "on fluid in said work piece, said testingplungerhaving a passageway therethrough for admitting fluid intosaidwork piece,

a. high pressure fluid source for supp y n 1 P sure fluid to saidclamping means andsaid testing plunger,1a low-pressure fluid'source forupplying fluid through said passageway intosaid assembly, said'pr'essing' cylinder-pistoni-assembly and said shielding means actuatingcylinder- --piston-assembly in' aprede'termined sequence,

' said shielding meansi' #11. --In: a testingapress, hydraulically"operable clampingmeans for inovably supporting and holding "a hollowworkpiece in testing position,

hydraulically operablepress'ing m'eansior exerting pressure on fluid insaidj-hollow work piece, a fluid source, a hydraulic circuitinterconnecting said fluid sour'ce and saidclamping and pressing meansfor supplying pressure fluid tosaid clampwork-piece, controlling meansinterposed between said low pressure fluid. source and saidpassagewayIfor admitting a predetermined quantity of fluidz'from saidlow pressure fluid source through 'ing' and-pressing means, andadjustable pressure responsive means for automatically establishing andmaintaining'a predetermined ratio between the clamping pressure of :saidclamping means and the pressure applied by said pressing means duringthe'testingoperation'; M w I 12. In a testing press, hydraulicallyoperable supporting means adapted :to movably support a hollow workpiece and clamp the same in testing 7 position, hydraulically operablepressing means for exerting pressure on fluid in :said hollow workpiGOi-l, pressure indicating means operably-non- -nectedwithsaidpressing means for indicating the pressure exerted by saidpressingmeans, a

"fluid-source adapted-to supply pressure fluid to said clamping meansand said pressing-means,

"and pressure responsive controlling means 'for 'saidmpassagewa y intosaid Work piece, and means associated withsaid controlling meansfor'selec- 'tively'int'errupting fluid connection between said workpiece and :said low pressure fluid source through said passageway.v v

14. In a testing press, clamping means for hydraulically supporting ahollow-workpiece and holding the same intestin'g position, liquidstorage means for storing liquid'tosb e unloaded into said work pieceforthete'sting of the same, means for filling said storage means" with apredetermined quantity-of liquid, adjustable means for maintaining theliquid :in said storagemeans at a predetermined level invaccordance withsaid predetermined;quantity;to be unloaded-in said 7 work -piece,=afluid operable testing plunger having a longitudinal bore therethroughand. being adapted to enter saidhollow work piece to exert pressure onliquidi-n said -work piece, means bydrauli'ca llyj; connected gwith saidbore in said plunger for conveying said predetermined quantity of liquidfromvsaidzstorage means intozsaid hollow work piece prior to the actualpressing operationgof said testing plunger;- means ;for;-interruptingfluid connection -.-betweenjsaid storage means, and said hollow workpiece during the pressing-operation of said testing; plunger, and meansfor supplying pressure fluid to said testing --p1unger; tocausetheelatter'to exert a pressing or testing operation.

o I "wALTEa'ERNs rf V i 1.134 B. LAWYER,

